Falcon Heavy! BT60-based with separating boosters

The Rocketry Forum

Help Support The Rocketry Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
So after fiddling around with different ways of making the upper booster hooks, I decided the best way was to use some of the polycarbonate sheet left over from the fins to make the actual hook part. If it were wood, it might split. Then I thought about how to firmly attach it to the side of the body tube. These will go on the sides of the separation point, so nothing can go TTW. I settled on doing it like so:

Polycarbonate hook sandwiched between two 3/16 strips of the hardest balsa I could find, with tiny hardwood rivets going through perpendicularly, all epoxied together. The balsa strips being twice as long leaves a perfect slot for the tab on the booster.




Here are the completed parts epoxied to the tube. I used BSI 15-minute, but it seemed more like 7-minute as that's when it started to get stringy. Might need a bit of sanding on this later at the finishing stage.




I also cut out slots into the upper part of the booster tubes to accommodate the hooks and then dabbed with thin CA to harden the edges. I plan on putting an extra 1/2" or so wrap of body tube at the top and then CA that, so as not to tempt the zipper gremlins when these separate at high speed. Hopefully.




This shows exactly how it fits at the top. The nose cones will be slotted to fit over this hook.




So... Before I got a Dremel, I tried cutting a slot into the BB nose cone using an x-acto. Kind of turned out hackey and rough. Then, after "splurging" on a $30 Dremel, I did the other one. This one came out much better looking.




Finally nearing completion of the construction. Launch is "6 months" away :lol:




Next is to finish up the recovery system for the boosters, mainly attaching the shock cord and small chutes. Then to finish up the recovery sys for the core. Somewhere in there I still have to do up 16 small epoxy fillets on the body tube-fin joints. I'm also thinking of building cardstock models of the landing legs to glue on the side. I'd need 12 of them but I think it might go fast once I do one. Construction phase should be complete at that point. Then comes finishing. Weather is getting better for paint so I might be able to start the primer/sand cycle. Once painted, I think I'll try printing a body-wrap for the core out of office paper since I have a good printer and see how that looks.

...and launch lugs. I always forget those. I'll be using 1/4" which seems appropriate for this size and weight.
 
Back
Top